The present invention relates to data storage and retrieval, and more particularly, to dynamic gain control used with adaptive equalizers in a read channel for reading data from a data storage medium.
In magnetic data storage, and particularly when storing data to and retrieving data from magnetic tape, a given tape drive, in order to be most useful, should be able to read as many different types of magnetic tapes as possible, from multiple vendors and having different layouts. The magnetic tapes that are read may be manufactured by any of several different manufacturers. Furthermore, legacy magnetic tapes having outdated formats and layouts should also be able to be read by the tape drive. Because of this, the read-detection channel of the tape drive should be able to adapt to variations in readback signals that it might receive, across a family of magnetic tapes having different manufacturers and/or layouts.
Thus, it is desirable that the read-detection channel has the ability to adapt to a wide range of signals while ensuring that the adaptation is controlled and optimal.